1. Field of the Invention
The present invention relates to a bearing for electric motor sealed with grease, and more particularly it relates to a bearing for electric motor sealed with grease, having small loss by friction, small noise and long life.
2. Description of the Related Art
Conventionally, various investigations have been made on bearing for electric motor to develop a bearing having small loss by friction, small noise and long life. Recently, in particular, global environmental problem is getting a great deal of attention, and advanced countries are obligated to make an effort to reduce waste of energy as less as possible. Various proposals have been made and improvement has been made on bearings used in every field, but it is the actual circumstances that further improvement is still required.
As one conclusion of energy saving problem, it is the demand of the times to use DC motors having good efficiency in place of AC motors.
In particular, in fan motors of air conditioners for household use, now it is the time to use DC motors having good efficiency in place of AC motors that still has the limit even after a converter is provided to change an output. Various proposals have been made to reduce energy loss and improvement has been made on bearings for electric motor used in every field, but it is the actual circumstances that further improvement is still required.